In the design of shock absorbers, a particular fluid/gas compression ratio for landing is chosen to provide optimization of the shock absorbing capabilities of the shock absorber. However, the shock absorbing capabilities of a conventional shock absorber are markedly affected by temperature changes. This is due to changes in the fluid/gas compression ratio caused by thermal variations. When the ambient temperature changes cause a change in the temperature of the shock absorber, the fluid inside the shock absorber expands or contracts according to a temperature increase or decrease, respectively. Since the fluid is essentially incompressible and there is a fixed total volume of fluid/gas inside the shock absorber, if the temperature changes the volume of the fluid increases or decreases, thereby causing the volume of the gas to decrease or increase, respectively. This temperature change thus alters the compression ratio of the shock absorber. If the temperature increases, the compression ratio increases and the shock absorber becomes "stiffer". Conversely, if the temperature decreases, the compression ratio decreases and the shock absorber becomes "softer". These changes can seriously impact the landing loads imposed on an airplane structure and the landing characteristics of the airplane, such as the maximum allowable landing weight of the airplane, which affects its load carrying capabilities, and the vertical descent speed at which the airplane can land, which restricts its flight patterns.
Accordingly, it is a general object of the present invention to provide an improved shock absorber.
It is another aspect of the present invention to provide a shock absorber which is thermally efficient.
It is a further advantage of the present invention to provide a shock absorber in which the effects of temperature changes on shock absorber efficiency are greatly reduced.
It is still another object of the present invention to provide a shock absorber in which the fluid/gas compression ratio is substantially unaffected by thermal variations.